ScummVM fullscreen on a Raspberry Pi TFT touchscreen

I managed to get ScummVM running on the 3.5" Waveshare touchscreen. This is obviously only nice, if it runs fullscreen. Have a look:



For this to work, you need to adjust your openbox configuration, assuming you are running a default Raspbian with LXDE / openbox. Edit .config/openbox/lxde-pi-rc.xml and add the following to the applications section:

   <application class="scummvm" name="scummvm">  
     <fullscreen>yes</fullscreen>  
   </application>  

You can switch between fullscreen and windowed mode by pressing Alt+F11, in the default openbox configuration.

Next, you need to install scummvm and the OpenGL software rasterizer, since the touch screen frame buffer does not support the hardware OpenGL engine that the Pi provides:

$ sudo apt-get install scummvm mesa-utils libgl1-mesa-dri libgl1-mesa-swx11

This will also install dri drivers and some OpenGL utilities, such as glxgears to test performance.

Now you want to tell ScummVM to actually use the OpenGL backend driver, or else it will not scale to, but rather use the default 2x scaler, which is too large for the 480x320 display. Easiest way to do this is to edit ~/.scummvmrc (you have to have run ScummVM at least once for this) and edit the [scummvm] section to have these lines:

[scummvm]
last_fullscreen_mode_width=480
last_fullscreen_mode_height=320
gfx_mode=opengl_nearest

If gfx_mode or the other lines already exist, edit them to your liking.

Installing an ads7864 based Raspberry Pi TFT touchscreen (Waveshare 3.5" LCD)

I have a Waveshare 3.5" TFT touch screen for the Raspberry Pi. Those displays come with some software to help set it up. Sadly, this only works for Raspbian based on Debian 7. The new Raspbian Debian 8 (Jessie) does not play well with this setup. So here is what I did to make it work.

First of all, you need to upgrade the kernel on your brand new Jessie installation:

$ sudo rpi-update
$ sudo power off

I had to do the power off, or else the Pi would show only a black screen after reboot. YMMV.

Next up, we need to change the boot parameters, i.e. the /boot/config.txt and /boot/cmdline.txt. Add the following to the end of /boot/cmdline.txt:

fbcon=map:10 fbcon=font:ProFont6x11 logo.nologo

This chooses a smaller font for the framebuffer console and turns off the boot logo.

Second, add the following lines to the end of /boot/config.txt:

dtparam=audio=on
dtparam=spi=on
dtoverlay=ads7846,cs=1,penirq=17,penirq_pull=2,speed=1000000,keep_vref_on=1,swapxy=1,pmax=255,xohms=60,xmin=200,xmax=3900,ymin=200,ymax=3900
dtparam=i2c_arm=on
dtoverlay=w1-gpio-pullup,gpiopin=4,extpullup=1

Next step is setting up all the kernel modules. Make sure /etc/modules contains exactly these line:

spi-bcm2835
snd-bcm2835
i2c-bcm2708
i2c-dev
ads7846
flexfb
fbtft_device

The options for these modules have to be put in a file called /etc/modprobe.d/lcd.conf:

options flexfb  width=320  height=480  regwidth=16 init=-1,0xb0,0x0,-1,0x11,-2,250,-1,0x3A,0x55,-1,0xC2,0x44,-1,0xC5,0x00,0x00,0x00,0x00,-1,0xE0,0x0F,0x1F,0x1C,0x0C,0x0F,0x08,0x48,0x98,0x37,0x0A,0x13,0x04,0x11,0x0D,0x00,-1,0xE1,0x0F,0x32,0x2E,0x0B,0x0D,0x05,0x47,0x75,0x37,0x06,0x10,0x03,0x24,0x20,0x00,-1,0xE2,0x0F,0x32,0x2E,0x0B,0x0D,0x05,0x47,0x75,0x37,0x06,0x10,0x03,0x24,0x20,0x00,-1,0x36,0x28,-1,0x11,-1,0x29,-3
options fbtft_device debug=3 rotate=90 name=flexfb speed=16000000 gpios=reset:25,dc:24
options ads7846_device model=7846 cs=1 gpio_pendown=17  keep_vref_on=1 swap_xy=1 pressure_max=255 x_plate_ohms=60 x_min=200 x_max=3900 y_min=200 y_max=3900

Next up are the X11 configurations. First, add a file /etc/X11/xorg.conf.d/99-calibration.conf with the following content:

Section "InputClass"
    Identifier "calibration"
    MatchProduct "ADS7846 Touchscreen"
    Option "Calibration" "126, 3734, 3892, 199"
    Option "SwapAxes" "1"
EndSection

You also need to edit /usr/share/X11/xorg.conf.d/99-fbturbo.conf. It should already exist, and you need to make it have this content:

Section "Device"
        Identifier      "Allwinner A10/A13 FBDEV"
        Driver          "fbturbo"
        Option          "fbdev" "/dev/fb1"
        Option          "SwapbuffersWait" "true"
EndSection

The change is setting the fbdev to /dev/fb1, which is the touchscreen, instead of /dev/fb0, which is the HDMI output.

Last but not least, you may want to install the input calibration tool:

$ sudo apt-get install xinput-calibrator

After all this, reboot and hopefully the Pi will reboot into a tiny X11 session on the touch screen.

You can calibrate the display by running this, e.g. via an ssh session:

$ DISPLAY=:0 xinput_calibrator 
Calibrating EVDEV driver for "ADS7846 Touchscreen" id=6
        current calibration values (from XInput): min_x=3932, max_x=300 and min_y=294, max_y=3801

Doing dynamic recalibration:
        Swapping X and Y axis...
        Setting calibration data: 2763, 2763, 2942, 2978
        --> Making the calibration permanent <-- span="">
  copy the snippet below into '/etc/X11/xorg.conf.d/99-calibration.conf' (/usr/share/X11/xorg.conf.d/ in some distro's)
Section "InputClass"
        Identifier      "calibration"
        MatchProduct    "ADS7846 Touchscreen"
        Option  "Calibration"   "2763 2763 2942 2978"
        Option  "SwapAxes"      "1"
EndSection

You simply have to replace the calibration and swap axes lines into your /etc/X11/xorg.conf.d/99-calibration.conf, which we created earlier.

How to setup mDNS lookups on the Raspberry Pi

I've got the new Raspberry Pi 2, and was setting it up the other day. The first thing that annoys me with vanilla Debian installations is that they don't have mDNS/zeroconf/avahi enabled by default. This technology is very useful, since it helps you to advertise services on you local network, lets you resolve host names without the need for setting up a DNS server and much more.

Especially the convenience of not having to remember IP-addresses for your machines is worth the work to set this up. With DHCP you might not even get the same IP for every machine every time.

For this to work, I asked a question over at the Linux & Unix StackExchange. So parts of this blog entry are taken from there.

First, you might want to install avahi on your RasPi;

sudo apt-get install avahi-daemon

This should help with the Pi being resolvable by name from other machines -- which also have to support mDNS. For example Macs will come with mDNS-lookup enabled. So you should be able to ping your Pi just by using its name plus the local-domain:

ping raspberrypi.local

Next, you want to install the client side name service support for mDNS:

sudo apt-get install libnss-mdns

Make sure that the /etc/nsswitch.conf contains this line:

hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4

There is probably already a line starting with "hosts:", which you can simple comment out with the #-sign.

For added convenience, you may want to add the sshd to the advertised services of avahi. Simply add a file /etc/avahi/services/ssh.service containing the following lines:

<?xml version="1.0" standalone='no'?><!--*-nxml-*-->
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
<service-group>
  <name replace-wildcards="yes">%h</name>
  <service>
     <type>_ssh._tcp</type>
     <port>22</port>
  </service>
</service-group>

This should let you use mDNS on you Pi, see the advertised services on you other machines in the local network. If you are using Plex Media Server (see this great post), it will also utilize avahi to advertise its services.

Autocompletion for C and C++ with Emacs 24

I have already done a blog post on auto completion using Emacs. But that was back in Emacs 23 days. Long ago...

Since then a lot has happened. Emacs 24 has been released, package managers like MELPA or ELPA have become standard, and company-mode seems to be winning against auto-complete. Also, clang has made huge strides forward.

So it is time to revisit the task of developing C or C++ using Emacs. I have put online an easy-to-install Emacs init.el that you can use as a start for your own development environment. I am using the OS X version of Emacs, but this should also work on Linux, given that you have clang and git installed.

You can install this init.el by issuing the following commands:

cd
git clone https://github.com/root42/yet-another-emacs-init-el
mkdir ~/.emacs.d
cd ~/.emacs.d
ln -snf ../yet-another-emacs-init-el/init.el .

The file will make sure that upon startup of Emacs all necessary packages are installed, like company, magit but also LaTeX tools like aucTeX or refTeX. You can disable this check (or individual packages) in the init.el.

The code is up on github, so feel free to fork and/or contribute.

When doing simple C++ programming using only standard libraries, you should be ready to go. For more complex projects, you have to tweak the clang parameters, so that the compiler will find the header files. Completion happens automatically after ".", "->" and "::" but also when pressing M-/. You can rebind this key in the init.el, of course. This is what the completion looks like:

My most commonly used keys that I have re-bound are as follows:

• f3 - Runs ff-find-other-file, trying to switch between header and implementation for C/C++ programs.
• f4 - Toggles the last two used buffers.
• f5, f6 - If tabbar is enabled (tabbar-mode), navigates back/forward through tabs.
• f7 - Toggle ispell dictionaries (german/english).
• f8 - Kill current buffer.
• f9 - Run compile.
• M-? - Run grep.
• M-n - Go to next error in compilation buffer.
• M-S-n - Go to previous error in compilation buffer.
• M->, M-< - Go to next/previous Emacs frame.
• M-/ - Run autocompletion using company mode.
• C-x o, C-x C-o - Go to next/previous Emacs window

Very nice is also the magit-mode, which is a very sane interface to git for Emacs. It looks like this:

You can run it by executing M-x magit-status. Just type ? to get online help. Magit uses simple one-character-commands, like s for stage, c for commit, p for push and so on.

Currently I am evaluating the integration of lldb into Emacs, but haven't come far enough to say that I have found a powerful and flexible interface, apart from the standard command line. So there's more to come, hopefully!

How to backup your Raspberry Pi SD-Card

In the following I will explain on how you can backup your Pi's SD-card, so that whenever it breaks down, you can simply restore the backup image to a fresh SD-Card. This may also help with tinkering, when you totally screwed up your Pi's Linux-installation. I will explain the first step specifically for Mac OS X, but you can do this similarly on other UNIXes and Linux, by using the mount and umount commands.

So, shut down your Pi using the command sudo shutdown -h now and remove the SD-card after the Pi has done so. Take the card and insert it into your Mac's SD-card slot.

First of all, we need to find out which disk device has been assigned to the card. We can do this with diskutil list:

user@mymacintosh:~ $ diskutil list                                                                

/dev/disk0                                                                                            

   #:                       TYPE NAME                    SIZE       IDENTIFIER                        

   0:      GUID_partition_scheme                        *512.1 GB   disk0                             

   1:                        EFI EFI                     209.7 MB   disk0s1                           

   2:                  Apple_HFS M4                      511.1 GB   disk0s2                           

   3:                 Apple_Boot Recovery HD             784.2 MB   disk0s3                           

/dev/disk1                                                                                            

   #:                       TYPE NAME                    SIZE       IDENTIFIER                        

   0:     FDisk_partition_scheme                        *15.9 GB    disk1                             

   1:             Windows_FAT_32                         58.7 MB    disk1s1                         

   2:                      Linux                         15.9 GB    disk1s2                           

Then unmount the card using diskutil unmountDisk:

user@mymacintosh:~ $ diskutil umountDisk /dev/disk1                                              

Unmount of all volumes on disk1 was successful                                                     

Next we will use dd to produce an image, which we can compress using bzip2, or pbzip2 for more performance. You can use MacPorts to install pbzip2.

user@mymacintosh:~ $ sudo dd if=/dev/disk1 | pbzip2 > raspberry_pi_$(date "+%Y-%m-%d").img.bz2 

31116288+0 records in                                                                                                           

31116288+0 records out                                                                                                        

15931539456 bytes transferred in 2347.692010 secs (6786043 bytes/sec)                                                           

Restoring the image is also easy:

user@mymacintosh:~ $ bunzip2 raspberry_pi_2014-03-22.img.bz2 | sudo dd of=/dev/disk1      

How to use find and rsync to copy a bunch of files to a local or remote destination

I use rsync a lot. And I use find a lot. You can use them both together, by using the magnificent xargs command. Two problems are there to solve: xargs usually just pastes the arguments from find at the end of the specified command. No way to specify the destination directory. Second, file names with spaces are a problem.

The solutions are:

• The -print0 option of find uses 0-bytes to separate results, instead of spaces and newlines
• The -0 option of xargs tells xargs to look for said 0-bytes
• The -J option of xargs allows us to tell xargs where to put the file names that we feed to it.

So let's put it together:

pi@raspberrypi ~ $ find . -name 'your*pattern.jpg' -print0 | xargs -J % -0 rsync -aP % user@host:some/dir/

Thanks to redeyeblind for the insightful blog post.

How to setup an OpenWRT router as a WiFi bridge to an Ethernet router

You can use an OpenWRT router or access point to connect WiFi enabled devices to a router, which only has wired Ethernet. For this to work, I am assuming you already have an access point or router running OpenWRT, in this case version 12.09, Attitude Adjustment.

Log into your router, using the LuCi frontend, and go to the Network/Interfaces tab:

There you should see your LAN device. Edit it to have an appropriate IP address from your local subnet. Most often your network will be 192.168.0.0 and your existing router will have the IP 192.168.1.1. But your mileage may vary...

Lets put in a static IP address, so we can find our router in case something goes wrong. Also make sure to set the netmask (in this case 255.255.255.0), gateway and DNS server (both probably should point to your router, 192.168.1.1).

Now go to the Physical Settings tab. Here, it's important to check "Bridge interfaces" and to select both the ethernet adapter, most likely eth0, and the wireless network. One of the ethernet devices will say "wan", if your are using a router instead of an access point for this. You don't want that device.

Hit "Save & Apply" when you are ready. And be sure to have the de-bricking guide ready, if something goes wrong...

How to run tmux via ssh instantly

With my Raspberry Pi, what I do very, very often is this:

localhost$ ssh raspberrypi.local    # Here I already type the next command and wait a while
raspberrypi$ tmux attach

This is all well and good, but sometimes the Pi is down, and I will attach to one of my local tmux sessions. Very annoying. Instead you could try to do this:

localhost$ ssh raspberrypi.local tmux attach
not a terminal

Well, that did no good. So a look at the man-page of ssh or a quick search reveals this gem:

localhost$ ssh raspberrypi.local -t tmux attach

This allocates a pseudo terminal, which is needed by tmux to function correctly. This is also done by ssh, if no command is given, but a login shell is spawned.

How to copy Mails from iCloud to GMail

You can use the fabulous imapsync tool to copy mails between IMAP servers. For example you can copy a certain folder from Apple's iCloud to Google's gmail:

imapsync \
   --noauthmd5 --ssl1 --ssl2 \
   --host1 mail.me.com --user1 'your.icloud.name' \
   --host2 imap.gmail.com --user2 'your.gmail.name@googlemail.com' \
   --folder 'your/folder/to/be/copied' --sep1 '/' \
   --prefix1 '' --prefix2 '[Google Mail]' --sep2 '/'

The important parts here are the user names for the IMAP servers. Note that you need to generate an application specific password, if you are using Google two factor authentication! Also important is the "[Google Mail]" IMAP prefix.

Edit: It seems gmail has a weird interpretation of all the IMAP folders and stuff. Since they are using labels, the above script might create a weird label for the copied emails, but they will be there nevertheless!

How to get a directory recursively with lftp

Using the command mget, you can fetch files with the program lftp. With mget -c you can continue an aborted download. But how do you download a directory recursively? No, mget -c -r does not work.

It is so simple:

mirror somedirectory

Don't forget to lcd into your download directory before.

Working around connection problems with Emacs Tramp

From time to time I have to edit files on a SunOS 5.10 server. I use Emacs with tramp for this. However, after some time I get this error message from tramp:

File error: Couldn't find exit status of `test -e ...

It seems that the ssh connection goes bad for some reason. After this you won't be able to save the file anymore. You can work around this by running M-x tramp-cleanup-all-connections and then saving again.

Avoiding page allocation failures on the Pi

Since I've been using my 256MB Model B Pi as a server, I had been getting regular page allocation failures of the following kind:

sshd: page allocation failure: order:0, mode:0x20

This is rather annoying and seems to affect stability as well, like disrupted ssh or smb connections. It seems that the kernel has a setting to affect the minimum free memory that it keeps for allocations, which may be too low. So in the /etc/sysctl.conf file you can edit the last lines to bump this value from 8 Mbegabytes to 16 Megabytes:

# rpi tweaks
vm.swappiness=1
vm.min_free_kbytes = 16184

Settings are effective after a reboot. For me, this seems to fix the problem. But to be extra sure, I also changed the memory split from 192/64 to 224/32. Since my Pi runs headless, 64 MBytes seemed too much simply for a framebuffer console that is not even used. So after these tweaks my Pi shows 216 MByte of available memory and is running for some days now without page allocation errors.

Delay warnings when using USB audio on the Raspberry Pi

My kernel.log and debug log files had grown to over 2 GBytes each. This was due to log messages of this kind:

delay: estimated 0, actual 133

As another blog stated, this can be fixed by adding a parameter to the sound-usb-audio module of Alsa. So I did the same thing, creating a file /etc/modprobe.d/snd_usb_audio.conf with this content:

options snd-usb-audio nrpacks=1

After restarting Alsa or a reboot, the problems were gone, the logfiles kept small.

The Raspberry Pi and Ralink rt2800 based WiFi dongles

I strongly discourage the usage of rt2800 based WiFi dongles with the Raspberry Pi. For some weeks I have been debugging why my Raspberry Pi freezes and crashes all the time. And it turns out that it is the WiFi dongle. I was using an Edimax EW-7711UTn, but the chip is also being used in other devices. There seems to be a bug report for the Raspbian kernel, and I have spent quite some time on the Raspberry forum at Stackexchange. Currently, I hooked up the Raspberry Pi via Ethernet directly to my router. This works fine, but the router is upstairs, while the Raspberry is supposed to be downstairs, connected to my stereo. So this is only a stopgap measure until I have found a WiFi dongle that does not crash the Pi. Hints are welcome.

Update: I now switched to a TP-Link TL-WN725N with a RTL8188CUS chip. This adapter is much smaller (no external antenna) and surprisingly also quite a bit faster. I achieve ~1.9 MByte/sec sustained point to point datarates via SMB. So far no crashes or other problems. I will continue testing, but it looks much better than with the Ralink chip.
Update 2: Almost four months into testing the RTL8188CUS based WiFi dongle and it runs absolutely fine. I have uptimes of almost a month without any problems. After that the Pi degrades due to some of the daemons leaking or memory fragmentation. But I think this is bearable!

How to make the mpdas run as a daemon

The other day I installed the mpdas, which is the audio scrobbler for the music player daemon. Since there's no debian package for the Raspberry Pi, I compiled mpdas from scratch and installed it. Now I don't want to run it manually each time the Raspberry Pi boots up. So I found a nice template for writing your own debian-style init-script. I changed it a little and also installed the daemon tool, to turn the interactive mpdas program into a daemon. Just run apt-get install daemon to install it. Then put the following file under /etc/init.d/mpdas and run update-rc.d mpdas defaults. Then mpdas will be run automatically upon boot. Oh, one more thing: put your mpdas configuration under /usr/local/etc/mpdasrc or adjust the DAEMONOPTS in the init script accordingly.

#!/bin/bash
### BEGIN INIT INFO
# Provides:          mpdas
# Required-Start:    $remote_fs $syslog $mpd
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# X-Interactive:     true
# Short-Description: Audio Scrobbler for mpd
# Description:       Starts the Audio Scrobbler for the mpd music player daemon.
### END INIT INFO

DAEMON_PATH="/usr/bin/"

DAEMON=daemon
DAEMONOPTS="-u pi -r -X /usr/local/bin/mpdas"

NAME=mpdas
DESC="The mpdas audio scrobbler for mpd"
PIDFILE=/var/run/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME

case "$1" in
start)
printf "%-50s" "Starting $NAME..."
cd $DAEMON_PATH
PID=`$DAEMON $DAEMONOPTS > /dev/null 2>&1 & echo $!`
#echo "Saving PID" $PID " to " $PIDFILE
 if [ -z $PID ]; then
     printf "%s\n" "Fail"
 else
     echo $PID > $PIDFILE
     printf "%s\n" "Ok"
 fi
;;
status)
 printf "%-50s" "Checking $NAME..."
 if [ -f $PIDFILE ]; then
     PID=`cat $PIDFILE`
     if [ -z "`ps axf | grep ${PID} | grep -v grep`" ]; then
  printf "%s\n" "Process dead but pidfile exists"
     else
  echo "Running"
     fi
 else
     printf "%s\n" "Service not running"
 fi
;;
stop)
 printf "%-50s" "Stopping $NAME"
     PID=`cat $PIDFILE`
     cd $DAEMON_PATH
 if [ -f $PIDFILE ]; then
     kill -HUP $PID
     printf "%s\n" "Ok"
     rm -f $PIDFILE
 else
     printf "%s\n" "pidfile not found"
 fi
;;

restart)
$0 stop
$0 start
;;

*)
 echo "Usage: $0 {status|start|stop|restart}"
 exit 1
esac

How to make the Raspberry Pi automatically restart the WiFi interface

My WiFi router sometimes goes haywire and the Pi won't notice when the WiFi connection is up again. So I wrote this little script:

#!/bin/bash                                   
                                              
TESTIP=192.168.1.1                            
                                              
ping -c4 ${TESTIP} > /dev/null                
                                              
if [ $? != 0 ]                                
then                                          
    logger -t $0 "WiFi seems down, restarting"
    ifdown --force wlan0                      
    ifup wlan0                                
else                                         
    logger -t $0 "WiFi seems up."            
fi                                                                    

You can put this script under /usr/local/bin and add the following line to the system wide /etc/crontab:

*/5 * * * * root /usr/local/bin/testwifi.sh

This will check every five minutes if the connection is still up, and restart it, if the router cannot be pinged. If you dislike all the syslog messages, you can comment them out in the script.
My corresponding /etc/network/interfaces looks like this (I uninstalled all the network managers):

auto lo                                                                                  
                                                                                         
iface lo inet loopback                                                                   
iface eth0 inet static                                                                   
        address 192.168.3.42                                                             
        netmask 255.255.255.0                                                            
                                                                                         
auto wlan0                                                                               
iface wlan0 inet dhcp                                                                    
      pre-up wpa_supplicant -Dwext -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf -B
      post-down killall wpa_supplicant ; rmmod 8192cu ; modprobe 8192cu                  
                                                                                         
iface default inet dhcp                                                                  

The wpa_supplicant.conf should be easy to generate, there are lots of guides on the web for this.

Attaching a USB sound card to the Raspberry Pi

Since my Raspberry Pi runs headless, and the analog audio output is not that great, I decided to add a USB sound card to my little machine. I took a Roland UA-1G, which I was using before on an OpenWRT machine. The device was immediately recognized:

Bus 001 Device 007: ID 0582:00ea Roland Corp.

However, ALSA will prohibit the card from becoming sound device #0, thus being the default. For that you have to comment out the following line in /etc/modprobe.d/alsa-base.conf:

# Keep snd-usb-audio from beeing loaded as first soundcard
#options snd-usb-audio index=-2

After rebooting or restarting ALSA, the Roland will become the default sound device:

$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: UA1G [UA-1G], device 0: USB Audio [USB Audio]
  Subdevices: 0/1
  Subdevice #0: subdevice #0
card 1: ALSA [bcm2835 ALSA], device 0: bcm2835 ALSA [bcm2835 ALSA]
  Subdevices: 7/8
  Subdevice #0: subdevice #0
  Subdevice #1: subdevice #1
  Subdevice #2: subdevice #2
  Subdevice #3: subdevice #3
  Subdevice #4: subdevice #4
  Subdevice #5: subdevice #5
  Subdevice #6: subdevice #6
  Subdevice #7: subdevice #7

How to turn the Raspberry Pi into a music server

I have set up my Raspberry Pi as a music and file server. My requirements were:

• Big local storage (HD), shared over WiFi
• Local music playing capability, remotely controllable
• AirPlay speaker capability

The means by which I fulfilled the requirements were:

• Platinum 1TB MyDrive and Edimax EW-7711UTn USB wireless adapter
• mpd Music Player Daemon
• shairport AirPort emulator

For the first part, I bought a WiFi adapter, the Edimax EW-7711UTn. This one works out of the box with Raspbian, using WPA encryption (Note: I switched to a RTL8188 based dongle by now). It identifies itself with lsusb as:

Bus 001 Device 004: ID 7392:7711 Edimax Technology Co., Ltd EW-7711UTn nLite Wireless Adapter [Ralink RT2870]

This can be easily configured using the wpa_gui tool that comes with the default Raspbian installation. Settings will be saved and restored upon reboot.

Second, I installed samba, samba-common and samba-common-bin for sharing my USB drive. The latter one is a Platinum MyDrive, which is attached to a powered Belkin 7-port USB hub, so that I only need two power supplies. One for the Raspberry Py, and one for the Hub and its attached devices. The MyDrive has been formatted with NTFS, so as to be easily mountable under Linux, OS X and Windows. I mount it using the standard /etc/fstab mechanism. Just added one line to the file:

/dev/sda1       /media/MyDrive  ntfs-3g defaults          0       0

The /etc/samba/smb.conf gets in its first iteration only one additional share, a write-for-all public share, as a big file dump: 

[BigDump]

    comment = Free for all

    read only = no

    path = /media/MyDrive/FreeForAll

    guest ok = yes

Note that literally everybody in your LAN can access this and write to it! You may want to fine tune this...

Now to the mpd. It is easily installed by doing apt-get install mpd. When configuring it via /etc/mpd.conf make sure to change the following lines:

music_directory         "/media/MyDrive/Music/"

password                "MyVeryOwnPassword@read,add,control,admin"
bind_to_address         "any"

Change the directory and password to your liking. Then restart the service or reboot you device. You can control the mpd using a magnitude of clients. For example Theremin for OS X or Mpod for iOS.

Finally, I would like to be able to use the RasPi as an AirPlay target for my Mac and my iOS devices. This can be done via shairport. There are already a lot of good howtos for shairport on the Raspberry Pi. So I refer you to one of those. Two things come to my mind, though:

1. The Net::SDP library, required by shairport, is not available on Raspbian by default. It is best to clone the github mirror, and go by its installation instructions. Installation via CPAN fails, plus CPAN needs huge amounts of RAM.
2. The configuration needs to be tweaked a bit. The /etc/init.d/shairport script should be tuned to a sensible name for your RasPi. 

This way, you will be able to see the RasPi in your AirPlay speakers list and it will be happily churning along.

Clementine Player

A couple of years back, I was a big fan of Amarok, the music player. Then came along a rewrite and version 2.0, and I also switched to OS X. The version 2.0 was not very nice, stable or useful. The OS X version was very hard to install, due to the KDE dependencies. So I ditched Amarok. I replaced it with CogX for a while, and now I am using the horrid iTunes and the wonderful mpd (together with MPoD and Theremin). But today I read about the Clementine Player. It's a cross platform Amarok 1.4 fork. And after 10 minutes of testing, I think it's wonderful!

Controlling MPD with the iPhone

I just installed mpd on an OpenWRT router. It works great and I can recommend using MPoD for controlling it. The whole thing looks like this then: